E. coli genotypes

[Nancy Linford]

Hi. Thank you all for your helpful replies in the past. I have a couple of
questions that have been bobbing around the lab

1) WHat is the difference between a RecA13 (HB101 cells) mutation and a
RecA1 (XL-i blue, etc...)? Both are listed as mutations which reduce
recombination. However, by experience, our plasmid recombines like mad in
RecA1 cells but is reasonably stable in RecA13 cells. Does anyone know the
difference?

2) Why do cells containing the F'episome need to be grown on minimal media
to maintain infectability? It would seem more likely that in a "stressful"
medium such as minimal they would be more likely to save their energy
and not maintain pilli. 
 
thanks!
nancy
_______________________________________________________________________________
Nancy Linford					UW Dept of Pharmacology, 357280
nantzee at u.washington.edu			f-428       543-8502
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If you go through a lot of hammers each month, I don't think it 
necessarily means you're a hard worker.  It may just mean that you have a
lot to learn about proper hammer maintenance.  
-- Deep Thoughts, by Jack Handey